1. Field of the Invention
This invention relates to an audio signal reproducing device. It is more particularly suitable for an application to audio devices such as a portable type tape players.
2. Background
Many people enjoy using portable type tape players privately by using earphones. In this type of tape player, as shown in FIG. 1, sound leakage from the earphone is considered undesirable. The higher the volume, the greater this undesirable sound leakage. Such sound leakage can be prevented by suppressing high frequency sounds.
However, as shown in FIG. 1, when only the high frequency sounds are suppressed, there is a deterioration in sound quality. Accordingly, the music is less enjoyable.
One of the methods used to reduce the sound leakage problem, as shown in FIG. 2, is to detect the level of sound (shown as characteristics K1 and K2) and to suppress the portion of the spectrum where the level of sound is high (as shown characteristics K11 and K12).
However, with this method the sound leakage is still not completely prevented. If the level of sound is increased in the tape player proper, sound leakage still occurs.